optional_interfaces.phpt

--TEST--
Optional interfaces work
--FILE--
<?php

interface ExistingInterface {}

class ImplementingOptionalInterface implements ?ExistingInterface {}
class SkippingOptionalInterface implements ?NonExistantInterface {}
class MultipleOptionalsExistingFirst implements ?ExistingInterface, ?NonExistantInterface {}
class MultipleOptionalsExistingLast implements ?NonExistantInterface, ?ExistingInterface {}
class MixedOptionalFirst implements ?NonExistantInterface, ExistingInterface {}
class MixedOptionalLast implements ExistingInterface, ?NonExistantInterface {}

interface ExtendingExistingOptional extends ExistingInterface {}
interface ExtendingNonexistantOptional extends ?NonExistantInterface {}

class ImplementsInheritedExisting implements ExtendingExistingOptional {}
class ImplementsInheritedSkipped implements ExtendingNonexistantOptional {}

$classes = [
    ImplementingOptionalInterface::class,
    SkippingOptionalInterface::class,
    MultipleOptionalsExistingFirst::class,
    MultipleOptionalsExistingLast::class,
    MixedOptionalFirst::class,
    MixedOptionalLast::class,
    ImplementsInheritedExisting::class,
    ImplementsInheritedSkipped::class,
];

foreach ($classes as $class) {
    echo "$class\n";
    echo '    class implements:'.implode(', ', class_implements($class))."\n";
    echo '    object implements:'.implode(', ', class_implements(new $class))."\n";
}

$interfaces = [
    ExtendingExistingOptional::class,
    ExtendingNonexistantOptional::class,
];

foreach ($interfaces as $interface) {
    echo "$interface\n";
    echo '    interface extends:'.implode(', ', class_implements($class))."\n";
}

?>
--EXPECT--
ImplementingOptionalInterface
    class implements:ExistingInterface
    object implements:ExistingInterface
SkippingOptionalInterface
    class implements:
    object implements:
MultipleOptionalsExistingFirst
    class implements:ExistingInterface
    object implements:ExistingInterface
MultipleOptionalsExistingLast
    class implements:ExistingInterface
    object implements:ExistingInterface
MixedOptionalFirst
    class implements:ExistingInterface
    object implements:ExistingInterface
MixedOptionalLast
    class implements:ExistingInterface
    object implements:ExistingInterface
ImplementsInheritedExisting
    class implements:ExtendingExistingOptional, ExistingInterface
    object implements:ExtendingExistingOptional, ExistingInterface
ImplementsInheritedSkipped
    class implements:ExtendingNonexistantOptional
    object implements:ExtendingNonexistantOptional
ExtendingExistingOptional
    interface extends:ExtendingNonexistantOptional
ExtendingNonexistantOptional
    interface extends:ExtendingNonexistantOptional